This is a continuation-in-part of my copending application Ser. No. 459,998 filed Jan. 21, 1983, now U.S. Pat. No. 4,547,860 granted Oct. 15, 1985.
The trend in computers is to add keys to match the need for access to more of the computer functions made available with modern computer chips. Hand held computers regularly employ 40 keys and desk top computers often have well over 100 as standard. Even so, keyboards have not kept pace with the proliferation of computer chip functions available in the art, literally numbering in thousands for a single standard chip. Thus, as computers become more powerful and compact, keyboards are becoming more bulky and confusing. This trend, in ergonomic terms, is hardly to be considered a good one, since in order to have computers used with ease by more people it is imperative that the user/computer interface be simplified both in structure and in logic.
Computer U.S. Pat. No. 3,892,958--Jul. 1, 1975 to C. C. Tung is exemplary of the trend by some manufacturers in the keyboards they offer. The objective is to reduce the number of computer keyboard keys, yet 35 keys are still used. Prefix keys (gold--f and blue--g) are added for use in activating the keyboard in alternative computer selection modes to permit the keyboard to select three different functions per key. This extends the range of a 39 key keyboard available in a Hewlett Packard Model 15C computer, for example, to make accessible more of the computer chip built-in operating functions and program modes, namely 96, but at a cost of additional keys. Still 96 functions are undoubtedly far less than the several hundred available on computer chips in the present state of the art. Thus, access to full capacities of the chips is not feasible with the prior art keyboards, and a relatively large number of keys is still required to significantly extend the keyboard capacity to select more functions available on the chip. With this type of computer an external catalog of available computer entry conditions not shown on the keys is necessary, for example, to show the various operating conditions available in the program mode. For these type of portable hand held computers, the programming manual usually takes up more volume than the entire computer, which is limited in size only by the dimensions of the keyboard and display because of the micro-electronics employed.
Furthermore, with the 39 keys (or more as required to process more of the modes available on current powerful chips) in a hand held pocket-sized computer, the keys have to be placed so close together that it is difficult to make choices manually without fingering a wrong key. Also a sequence of reasoned selections must be made on prior art keyboards that interrupts the mental process and thereby introduces many opportunities for potential error into the key selection process.
This potential for error in manual selection of computer functions is even more pronounced whenever there are routines performed which are not indicated visibly on the keyboard in easy to identify and follow notation. Prior art keyboards have not resolved the problem of how to indicate two or more successive keystrokes necessary to complete some of the selectable functions or programs except for the aforesaid example which color codes a prefix key with a code abbreviation of the functions made accessible thereby. If complex key stroke sequences for various functions need be memorized or intermediate reference made to an instruction manual, the propensity for error is increased by the further interposition of unrelated thought processes. Thus, it has not been possible to provide access directly adjacent the keyboard keys of the necessary information for using a computer to perform several functions in many modes of operation. This is particularly true for pocket-sized computers where keyboard space is necessarily limited. Even desk-top computers which have to be programmed by mathematics and engineering oriented persons who are not expert typists are difficult for some users as they must "hunt and peck" among the more than one hundred keys which are usual on such keyboards.
The computer U.S. Pat. No. 3,892,958 does provide a limited amount of flexibility to the use of keys on the keyboard as identified by visible keyboard legends. Thus, the keyboard is usable in three different modes for function selection. To activate the two additional modes a manual selection of a color coded key is required such as gold (f) and blue (g) to correspond to three color coded legends for the keys on the keyboard panel facing or key. The limitation of this system, similar to the shift key on the typewriter, is to substantially triple the number of functions accessible by the keyboard. There is no way taught in the prior art for using substantially all the functions available from the computer chip with a simple keyboard having a few keys.
Clearly there is a bottleneck not resolved in the prior art, namely a computer-keyboard system that will provide with a reasonably small number of keys complete access to a general computer's wide range of modes of operation as well as to enter numerical digits, alpha characters and other data or instructions.
Furthermore, with this significant increase in key functions available, it is a most complex and difficult problem to teach relatively unskilled persons to operate the computer under all operating conditions. The prior art relating to pocket-sized general purpose computers requires instruction manuals many times larger than the computer containing complex operating instructions and tables. This is another significant problem not resolved in the prior art.